Related Party Transactions (Details) (USD $)			3 Months Ended					3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Alliance Building Services	Mar. 31, 2013 Alliance Building Services	Mar. 31, 2014 A-List Marketing, LLC	Mar. 31, 2013 A-List Marketing, LLC	Mar. 31, 2014 Nancy Peck and Company sqft	Mar. 31, 2014 Entity with Stephen L Green ownership interest	Mar. 31, 2013 Entity with Stephen L Green ownership interest
Related Party Transactions
Profit participation from related party			$ 900,000	$ 1,000,000
Related party expenses			3,500,000	4,100,000	17,800	2,400
Space at 420 Lexington Avenue leased (sqft)							1,003
Lease rent due per year							35,516
Increased lease rent due per year beginning in year seven							40,000
Property management fees from related party								104,800	118,200
Amounts due from/to related parties
Due from joint ventures	2,651,000	2,376,000
Other	17,296,000	6,154,000
Related party receivables	$ 19,947,000	$ 8,530,000